如果方向关闭，我正在使用以下代码旋转上传的 jpeg 图像。我只遇到从 iPhone 和 Android 上传的图片的问题。

if(move_uploaded_file($_FILES['photo']['tmp_name'], $upload_path . $newfilename)){
            chmod($upload_path . $newfilename, 0755);
            $exif = exif_read_data($upload_path . $newfilename);
            $ort = $exif['IFD0']['Orientation'];
            switch($ort)
            {

                case 3: // 180 rotate left
                    $image->imagerotate($upload_path . $newfilename, 180, -1);
                    break;


                case 6: // 90 rotate right
                    $image->imagerotate($upload_path . $newfilename, -90, -1);
                    break;

                case 8:    // 90 rotate left
                    $image->imagerotate($upload_path . $newfilename, 90, -1);
                    break;
            }
            imagejpeg($image, $upload_path . $newfilename, 100);
            $success_message = 'Photo Successfully Uploaded';
        }else{
            $error_count++;
            $error_message = 'Error: Upload Unsuccessful<br />Please Try Again';
        }

我从 jpeg 读取 EXIF 数据的方式有问题吗？它没有像预期的那样旋转图像。

当我运行 var_dump($exif); 时会发生这种情况

array(41) {
    ["FileName"]=> string(36) "126e7c0efcac2b76b3320e6187d03cfd.JPG"
    ["FileDateTime"]=> int(1316545667)
    ["FileSize"]=> int(1312472)
    ["FileType"]=> int(2)
    ["MimeType"]=> string(10) "image/jpeg"
    ["SectionsFound"]=> string(30) "ANY_TAG, IFD0, THUMBNAIL, EXIF"
    ["COMPUTED"]=> array(8) {
        ["html"]=> string(26) "width="2048" height="1536""
        ["Height"]=> int(1536)
        ["Width"]=> int(2048)
        ["IsColor"]=> int(1)
        ["ByteOrderMotorola"]=> int(1)
        ["ApertureFNumber"]=> string(5) "f/2.8"
        ["Thumbnail.FileType"]=> int(2)
        ["Thumbnail.MimeType"]=> string(10) "image/jpeg" }
        ["Make"]=> string(5) "Apple"
        ["Model"]=> string(10) "iPhone 3GS"
        ["Orientation"]=> int(6)
        ["XResolution"]=> string(4) "72/1"
            ["YResolution"]=> string(4) "72/1" ["ResolutionUnit"]=> int(2) ["Software"]=> string(5) "4.3.5" ["DateTime"]=> string(19) "2011:09:16 21:18:46" ["YCbCrPositioning"]=> int(1) ["Exif_IFD_Pointer"]=> int(194) ["THUMBNAIL"]=> array(6) { ["Compression"]=> int(6) ["XResolution"]=> string(4) "72/1" ["YResolution"]=> string(4) "72/1" ["ResolutionUnit"]=> int(2) ["JPEGInterchangeFormat"]=> int(658) ["JPEGInterchangeFormatLength"]=> int(8231) } ["ExposureTime"]=> string(4) "1/15" ["FNumber"]=> string(4) "14/5" ["ExposureProgram"]=> int(2) ["ISOSpeedRatings"]=> int(200) ["ExifVersion"]=> string(4) "0221" ["DateTimeOriginal"]=> string(19) "2011:09:16 21:18:46" ["DateTimeDigitized"]=> string(19) "2011:09:16 21:18:46" ["ComponentsConfiguration"]=> string(4) "" ["ShutterSpeedValue"]=> string(8) "3711/949" ["ApertureValue"]=> string(9) "4281/1441" ["MeteringMode"]=> int(1) ["Flash"]=> int(32) ["FocalLength"]=> string(5) "77/20" ["SubjectLocation"]=> array(4) { [0]=> int(1023) [1]=> int(767) [2]=> int(614) [3]=> int(614) } ["FlashPixVersion"]=> string(4) "0100" ["ColorSpace"]=> int(1) ["ExifImageWidth"]=> int(2048) ["ExifImageLength"]=> int(1536) ["SensingMethod"]=> int(2) ["ExposureMode"]=> int(0) ["WhiteBalance"]=> int(0) ["SceneCaptureType"]=> int(0) ["Sharpness"]=> int(1) }

最佳答案

基于 Daniel 的代码，我编写了一个函数，它可以在必要时简单地旋转图像，而不需要重新采样。

GD

function image_fix_orientation(&$image, $filename) {
    $exif = exif_read_data($filename);
    
    if (!empty($exif['Orientation'])) {
        switch ($exif['Orientation']) {
            case 3:
                $image = imagerotate($image, 180, 0);
                break;
            
            case 6:
                $image = imagerotate($image, 90, 0);
                break;
            
            case 8:
                $image = imagerotate($image, -90, 0);
                break;
        }
    }
}

单行版本(GD)

function image_fix_orientation(&$image, $filename) {
    $image = imagerotate($image, array_values([0, 0, 0, 180, 0, 0, -90, 0, 90])[@exif_read_data($filename)['Orientation'] ?: 0], 0);
}

ImageMagick

function image_fix_orientation($image) {
    if (method_exists($image, 'getImageProperty')) {
        $orientation = $image->getImageProperty('exif:Orientation');
    } else {
        $filename = $image->getImageFilename();
        
        if (empty($filename)) {
            $filename = 'data://image/jpeg;base64,' . base64_encode($image->getImageBlob());
        }
        
        $exif = exif_read_data($filename);
        $orientation = isset($exif['Orientation']) ? $exif['Orientation'] : null;
    }
    
    if (!empty($orientation)) {
        switch ($orientation) {
            case 3:
                $image->rotateImage('#000000', 180);
                break;
            
            case 6:
                $image->rotateImage('#000000', 90);
                break;
            
            case 8:
                $image->rotateImage('#000000', -90);
                break;
        }
    }
}

关于PHP read_exif_data 和调整方向，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/7489742/